Anti-inflammatory Compounds Produced in Hairy Roots Culture of Sphaeralcea Angustifolia

Abstract Sphaeralcea angustifolia (Cav) G. Don is used in traditional Mexican medicine to treat inflammations and gastric disease. Its anti-inflammatory and immunomodulatory activities in mice and rats acute and chronic models have been attributed mainly to scopoletin. Scopoletin reduced joint inflammation, the number of new vessels, production of endogenous angiogenic inducers, and reversed the histopathological alterations in rat adjuvant-induced arthritis. Tomentin and sphaeralcic acid from S. angustifolia cells in suspension proved anti-inflammatory and immunomodulatory activities in mice kaolin/λ-carrageenan-induced arthritis. Transformed roots of S. angustifolia have been proposed as active compounds producers. A high transformation frequency mediated by Agrobacterium rhizogenes ATCC15834/pTDT was obtained from nodal segments (59.5 ± 10.5%, 145 hairy root lines) and leaves (40.0 ± 25, 52 hairy root lines) of 2-month-old plantlets. Among seven lines selected according to their phenotypic characteristics and growth index, the SaTR N7.2 line presented the highest sphaeralcic acid production (17.6 ± 1.72 mg/g DW); this production was 440-fold superior to that reported in S. angustifolia wild plants, and in comparison to cells in the suspension of S. angustifolia in MS medium with nitrate restriction this was 263-fold higher when cultured in flasks and 5-fold higher in a stirred-tank type bioreactor. The SaTR N7.2, SaTR N5.1, SaTR N7.1, and SaTR N15.1 lines excreted sphaeralcic acid into the culture medium at similar levels. Genetic transformation of hairy roots was confirmed by amplifying a 490 bp fragment of the rolC gene. S. angustifolia hairy root cultures producers of scopoletin and sphaeralcic acid can be stressed by nitrate reduction and/or copper increased to stimulate scopoletin and sphaeralcic acid production.